The key moment came when NBC’s Chuck Todd asked Senator Landrieu, who is locked in a tight contest for reelection, why Obama’s approval ratings are so poor in her state. First she noted that his energy policies work against him in Louisiana, whose economy is dependent on gas and oil production. Then she brought up race.

“I’ll be very, very honest with you,” said Landrieu. “The South has not always been the friendliest place for African-Americans. It’s been a difficult time for the president to present himself in a very positive light as a leader.”

Republicans took umbrage. The state’s GOP chairman, Roger Villere, issued a statement saying that the implications of Landrieu’s words were “insulting to me and to every other Louisianian.” Lousiana Gov. Bobby Jindal, an Indian-American, called them “divisive” in a statement of his own.

Right-leaning pundits said Landrieu, who’s trailing Rep. Bill Cassidy (R) in the polls with only days to go, is getting desperate as she sees her chance to win a fourth term in office slipping away.

“There may be people who harbor racist and sexist prejudices in Louisiana, but there are such people in every state, and Louisiana has twice elected a person of color as governor and a woman as Senator three times in a row,” writes conservative Ed Morrissey at Hot Air.

Yes, that’s true. But it some ways Landrieu’s comments were banal, according to other commentators. From the late 1960s, into the ’80s and ’90s, the GOP’s southern strategy gave up on winning black votes and looked to benefit from the region’s racial polarization in other ways, writes Nia-Malika Henderson at The Fix at the Washington Post.

Then-RNC chairman Ken Mehlman said this directly in 2005 when he appeared at an NAACP event and apologized for the party’s past actions.

“The racial history of the South has played out at the ballot box. It exists. Landrieu isn’t breaking any new ground here. She is however breaking an unwritten rule in politics – it’s best not to talk about race, unless it’s about how far we’ve come,” writes Ms. Henderson.

Polls show Mr. Obama is indeed very unpopular with Louisiana whites.

According to a September CNN survey, Obama’s job approval among whites in the state is 17 percent. Among whites nationally, it’s about 32 percent, according to a recent Fox News poll.

But the president’s ratings among Louisiana African-Americans more closely mirror his national numbers.

Among non-whites in Louisiana, Obama’s job approval is 76 percent. Nationally, it’s 81 percent, according to the Fox survey.

There could be many reasons for this racial disparity, of course. The most obvious is that Louisiana whites are simply very conservative. Pollsters have found it almost impossible to accurately measure racial animus anywhere in America. There’s a strong social incentive to conceal racial feelings from inquisitive interviewers.

One preliminary effort to get around this involved a study that used derogatory Google searches to try and measure the votes Obama may have lost due to race.

Published in the October 2014 issue of the Journal of Public Economics, the study mined Google data to find uses of the “n” word by state. It estimated that Obama lost about four percentage points in the national vote in each of his presidential elections due to prejudice.

The state which had the highest rate of derogatory search using a racial expletive was West Virginia. Close behind, in second, was Louisiana.